Does the veterinarian think this may be a passing ailment or a long term problem?
I nursed a cat with kidney problems along for a couple years. It is easy, fortunately, to give subcutaneous fluids to a cat because it has loose skin. I used a heating pad to gently bring the bag of fluid to a cat body temperature (poor kitty, the one and only time I tried to use refrigerated fluid, she survived it but was one very shivery cat). I would talk to the cat and say “I know, a nuisance” when I poked. She was quite patient with me. Try to poke in different places each time so you are not poking through calloused skin which needs more force and is more painful to the cat.
Eventually her problem got so bad that it would have needed dialysis, not just fluids, and at that point out of pity for the cat I had her put out. But if this is a passing problem, like for a kidney infection, I think you may find the cat to endure it well and only lose a few of its proverbial lives in the process.
I second his post. : )
Thank you for those tips. Our first time will be in the morning. I’m a little nervous. We will warm it up first then.